Process and apparatus of hydrocarbon oil conversion



Dec. 5, 1933. J ALTHER 7 1,937,863

PROCESS AND APPARATUS OF HYDROCARBON OIL CONVERSION Original Filed Jan. 51. 1925 O O Q patented flee. 5, 1933 PROCESS AND APPARATUS F HYDRO- CARBON on. CONVERSION Joseph G. Alther, Chicago, Ill., assignor to Universal Oil Products Company, Chicago, Ill., a corporation of South Dakota Continuation of application Serial No. 5,946

January 31,1925. This application January 11, 1932. SerialNo. 586,037

2 Claims.' (01. 196-48) This application is a continuation of my application Serial No. 5,946, filed January 31, 1925.

This invention relates to process and apparatus of hydrocarbon conversion, and refers more par- 5 ticularly to the treatment of heavy carbon-forming oils under heat to produce maximum yields of commercial products therefrom. One of the biggest problems confronting the oil refining industry at the present day is the problem of how to treat heavy carbon-forming oils to produce maximum yields of higher commercial products therefrom without precipitating so much carbon in the system that the cost of refining is prohibitive. This, for the reason that I .15 the apparatusflmust be shut down for cleaning and removal of the precipitated carbon so frequently, and the cost of the apparatus remaining idle, coupled with the cost of actual cleaning, forms an overhead which makes it unprofitable to treat. 2o such oils.

The specific embodiment of the present inven tion is. directed to the successful commercial treatment of these heavy carbon-forminghydro carbon oils, and the various objects and advan- 2 5 tages of the invention will appear from the detailed description which follows.

.Inthe drawing, the single figure is a diagrammatic side elevational view of an oil treating apparatus in which my invention may be carried out.

.30 Before going into a detailed d'escription of this apparatus, it may be well to here briefly describe the operation of the process.

The heavycarbon-forming hydrocarbonoilis subjected to a temperature substantially less than A thetemperature of conversion, for instance, the

explained, maybe utilized'as the heating medium. This oil is not subjected to the conversion temperature, noris-it causedto pass through the waste heat from the process as will be hereinafter 40main heating tubes. This primarily heatedheavy oil may be discharged into an enlarged vertical reaction chamber where separation of the lighter ends in the form of vapors, and the precipitation of carbon will take place. This chamber is preferably unheated.

The lighter ends are removed in the form of vapors while the heavy unvaporized portions re- *main in the chamber in a substantial body of primarily heated; oil. The vaporized portions are subjected to dephlegmation, the reflux condensateof this dephlegmation being subjected totemperatures of conversion, tobring said condensate oil to a conversion temperature.-

heated condensate oil is then discharged into the same vertical reaction chamber where themajor oil through the heat interchanger the This highly.

portion will vaporize. The constant introduction of this highly heated condensate oil will cause the body of unvaporized residue maintained in the reaction chamber to be further heated, resulting in the release of further lighter ends. The vapors which are not condensed in the dephlegmator will condense in theusual manner and may be collected as distillate.

Referring in detail to the drawing, 1 designates an inlet pipe communicating with any source of oil supply such as storage or the like, and through which is introduced the heavy carbon-forming hydrocarbon oil to the suction side of the pump 2. The discharge or exhaust side of the pump communicates with the line 3 in which is interposed the valve 4 forcing the oil upward to the closed coil 5 supported in the upper part of the dephlegmator 6. hits passage to the closed coil 5, the oil in the: pipe 3 may be bypassed through the heat interchanger 7 by means of the pipes 8 5 and valves 9, valve 10 being closed. Where it is not desired to introduce heavy carbon-forming valves 9 are closed, and the valve 10 opened. Valve 11 is an auxiliary valve useful for the purpose of more .80 accurate regulation. The carbon-forming oil passing through the closed coil 5 in the upper part of the dephlegmator will be partially heated due to contactwith the vapors rising in the vertical dephlegmator as will be hereinafter explained,

and is discharged intothe line 12 to heating coils 13, from which it is returned through the line 14 in which is interposed valve 15, to the continuing line 16. A valve 17 is interposed in the line 16 between the inlet and outlet connections of the lines 12 and 14. The line16 discharges the heated oil onto a cone shaped deflector 18 which causes the liquid to spread in a thin film, thereby greatly assisting its vaporization by reason of its exposed surfaces, said cone shaped deflector being supported in the interior of an enlarged vertically positioned expansion chamber 19, which may be insulated as shown at 20, and which may be provided with the manhole plates 21 for the purpose of cleaning. This vertical reaction chamber is also provided at various points intermediate its height with the residue draw-01f lines 22 in which are interposed valves 23, and with the vapor outlet 24.

Instead of being discharged onto the coneshaped deflector 18, the valve 25 may be closed,

fvvith the transfer line 23, in which is interposed valve 29, the continuation of the by-pass 26 discharging directly into the upper portion of the interior of the reaction chamber 19. The purpose of this will be hereinafter explained. The lighter ends which vaporize in the reaction chamber 19, discharge through the vapor outlet 24 in which is interposed valve 30 communicating with the lower portion of the vertical dephlegmator 6. The vapors in their passage through this vertical dephlegmator are subjected to the cooling action of the closed body of oil flowing through the closed coil 5, and likewise transmit a portion of their heat to the oil passing through the closed coil 5. This cooling effect on the vapors passing through the dephlegmator, causes a certain portion of the heavy portions of these vapors to condense, this condensate being drawn off into the dephlegmator leg 31. The uncondensed portions of the vapors after passage through the dephlegmator .are discharged through the vapor outlet 32, passing in a closed path through the heat interchanger '7, valve 33 being interposed in the line 32. These vapors are then subjected to condensing action in the condensing coil 34 mounted in condensing box 35, discharging into the connecting line 36 in which is interposed valve 37, to the receiver 38 which, is equipped with the usual sight glass gauge 39, liquid draw-off 40, controlled by valve 41, and pressure relief pipe 42, controlled by valve 43.

Returning now to the dephlegmator leg 31, a portion of the reflux condensate may be diverted through the line 44, valve 45 being opened, the purpose being to discharge the portion diverted into the interior of the vertical reaction chamber. The balance passes down thereflux leg 31, and flows through the pipe 46 to the heating coils 4'7 mounted in the side fired furnace 48. This side fired furnace 48 is provided with the combustion chamber 49 heated by means of burners 50, the generated gases of combustion passing upwardly in the combustion chamber through the flues 51 and downwardly in the cracking chamber 52 countercurrent to the flow of oil through the heating coils 47, the spent gases of combustion being discharged through the stack 53.

The reflux may be forced to the heating coils under a hydrostatic pressure regulated by the height of the reflux leg 31, or the valve 54 in said line 46 may be closed, and the oil caused to pass through the by-pass 55 in which is interposed a force pump 56 and valve 5'7. An auxiliary valve 58 is provided.

In some cases it may be desirable to divert a certain amount of the reflux condensate from the 'line 46 through the by-pass 59, valve 60 being open, discharging the portion diverted in the line 12 for the purpose of diluting the heavy carbonforming oil flowing therethrough and increasing its velocity. The valve 58 in this instance would be slightly throttled, as it is not desired to divert any great amount of the reflux condensate into the line 12. Similarly, a certain portion of the heavy carbon-forming oil after passing through the heating coil 13 may be diverted into the line 46 by means of the by-pass 61 and valve 62. It is preferable that only a small portion, if any, of this carbon-forming oil be diverted into the reflux condensate line going to the heating tube 4'7. An auxiliary drain 63, controlled byvalve 64, is provided at the bottom of the vertical reaction chamber.

Briefly describing the operation, it may be as follows:

The heavy carbon-forming oil is forced by means of the pump 2 through the heat interchanger and closed coil 5 in the dephlegmator 6, and through the heating coils 13 in a closed path discharging into the vertical reaction chamber, Where separation of the lighter fractions will take place with consequent precipitation of carbon. The temperature to which said heavy carbonforming oil has been subjected has been carefully regulated, so that its highest temperature is materially below the temperature ordinarily required for a complete conversion.

Therefore, there will be no premature decomposition in its closed path of travel, and therefore, no separation and deposition of carbon, it being desirable that all carbon deposition and accumulation take place in the enlarged unheated vertical reaction chamber. The unvaporized portion of this heavy carbon-forming oil is maintained in a substantial body in said chamber, the vapors being continually withdrawn through the pipe 24 and subjected to dephlegmation; the reflux condensate from said dephlegmation is then subjected to cracking conditions and to a conversion temperature in heating tubes mounted in the same furnace, if desired, as is shown. The major portion of said heated condensate will vaporize immediately upon its discharge into the vertical reaction chamber, the heat therefrom assisting in the vaporization of light fractions still entrained in the liquid body of oil maintained in said chamber.

As an illustration of the temperatures and pressures, which may be employed to carry out my invention, the heavy carbon-forming oil is preferably not heated above a temperature of 400 to,

450 F., whereas the condensate passing through the heating coils 4'? is raised to a temperature of say, 800 to 900 F. A uniform pressure may be maintained on the entire system, or the oil passing through the heating coils 47 may be maintained at a higher pressure. The entire system may be maintained under an atmospheric pressure, if desired, it being understood, of course, that enough pressure must be supplied to overcome friction;

The heavy carbon-forming oil instead of being heated by the waste heat of the system as explained, may be subjected in a separate zone to a temperature as explained. However, the economy of the present arrangement will be immediately apparent to those skilled in the art. The heavy unvaporized portions may be withdrawn from time to time through the residue draw-offs 22, the valves 23 being opened, a plurality of said draw-offs being provided at various heights in order that the accumulation of carbon being built up in the reaction chamber will not interfere with the withdrawal of this residue.

As explained, the primarily heated carbonforming oil may discharge directly into the vertical reaction chamber 19, being deflected by the deflector 18, or it may be combined with the heated condensate being introduced through the transfer line 28, said combined mixture being introduced to the top of the reaction chamber. The vapors leaving the top of the dephlegmator through the vapor outlet 32 may be controlled in temperature by introducing other cooling mediums to said dephlegmator 6 other than the raw oil being passed in a closed path through the coil 5.

It is to be noted that the heavy carbon-forming oil does not pass through the main heating tubes, but is gradually heated to a temperature below the temperature of conversion. The by-pass 44 is particularly useful where a large through-put is 

